Bottom Line:
In contrast to other studies, the intramuscular fat content (IMF) did not increase in animals of groups fed a reduced protein diet and vegetable oils.The growth performance and meat quality of the longissimus muscle was not affected by the diet, but the average daily gain (ADG) and drip loss were affected.The muscle fatty acid concentrations were significantly affected by the diet, resulting in higher n-3 FA concentrations up to 113 mg/100 g muscle and lower n-6/n-3 PUFA ratio for pigs fed linseed oil-containing high- and reduced protein diets, compared to sunflower seed oil-containing diets.

ABSTRACTThe present study investigated the effect of a reduced protein diet in combination with different vegetable oils (sunflower seed oil or linseed oil) on carcass traits, meat quality and fatty acid profile in porcine muscle. Forty male Landrace pigs were allocated into four experimental groups (each n = 8) and one control group (n = 8) at a live weight of approximately 60 kg. The pigs were fed ad libitum from 60 kg to 100 kg live weight and restricted to 2.8 kg/day until they reached 120 kg. In contrast to other studies, the intramuscular fat content (IMF) did not increase in animals of groups fed a reduced protein diet and vegetable oils. The IMF ranged between 1.2% and 1.4%. The growth performance and meat quality of the longissimus muscle was not affected by the diet, but the average daily gain (ADG) and drip loss were affected. The muscle fatty acid concentrations were significantly affected by the diet, resulting in higher n-3 FA concentrations up to 113 mg/100 g muscle and lower n-6/n-3 PUFA ratio for pigs fed linseed oil-containing high- and reduced protein diets, compared to sunflower seed oil-containing diets.

Mentions:
The effects of dietary PUFA supplements, mainly linseed, rapeseed or sunflower seed oils, cake or seeds, on pig performance and fatty acid composition of tissues have been investigated intensively. It is known that feeding a linseed diet increases the n-3 PUFA content and decreases the n-6/n-3 fatty acid ratio in all tissues, whereas feeding sunflower seed leads to an increase in the n-6 PUFA contents due to the direct incorporation of the dietary PUFA into pig tissues [7,11,20,21]. The single fatty acid concentrations of the longissimus muscle in pigs are shown in Table 5, and the selected total fatty acid concentrations are presented in Figure 1. The muscle fatty acid concentrations of the present study appeared to be significantly affected by the diet, resulting in significantly higher n-3 FA concentrations (up to 113 mg/100 g muscle) in linseed oil-containing high- and reduced protein diets, compared to sunflower seed oil diets; only docosahexaenoic acid (22:6n-3, DHA) was not significantly increased. In most of the previous studies, the use of n-3 PUFA-rich vegetable oils showed no or only small effects on the intramuscular DHA level [7,15,21,22]. Feeding linseed oil-containing HPD- and RPD diets significantly decreased the concentration of single and total n-6 PUFA in longissimus muscle of pigs compared with the sunflower seed oil-containing fed groups and the control group (Table 5 and Figure 1). Consequently, the high level of n-3 PUFAs, which are beneficial for human nutrition, and the lower level of n-6 PUFAs in pigs fed linseed oil-containing diets caused a beneficially low n-6/n-3 PUFA ratio in the muscle compared with sunflower seed oil containing diets and the control diet. The n-6/n-3 PUFA ratio was 1.8:1 in muscle of pigs fed linseed oil containing HPD- and RPD diets, which corresponds to the n-6/n-3 PUFA ratio recommended by the German Nutrition Society (≤5:1) [23]. The concentrations of single saturated and total saturated fatty acids (SFA) were not affected by either the protein content or the type of oil supplement (Table 5 and Figure 1). Other studies showed that feeding a low protein diet with an increased IMF level resulted in elevated concentrations of 14:0, 16:0 and total SFAs, as a reflection of the higher IMF contents [19]. Additionally, oleic acid (18:1cis-9), the most abundant fatty acid in pig muscles, and total monounsaturated fatty acids (MUFAs) were not affected by the different dietary treatments.

Mentions:
The effects of dietary PUFA supplements, mainly linseed, rapeseed or sunflower seed oils, cake or seeds, on pig performance and fatty acid composition of tissues have been investigated intensively. It is known that feeding a linseed diet increases the n-3 PUFA content and decreases the n-6/n-3 fatty acid ratio in all tissues, whereas feeding sunflower seed leads to an increase in the n-6 PUFA contents due to the direct incorporation of the dietary PUFA into pig tissues [7,11,20,21]. The single fatty acid concentrations of the longissimus muscle in pigs are shown in Table 5, and the selected total fatty acid concentrations are presented in Figure 1. The muscle fatty acid concentrations of the present study appeared to be significantly affected by the diet, resulting in significantly higher n-3 FA concentrations (up to 113 mg/100 g muscle) in linseed oil-containing high- and reduced protein diets, compared to sunflower seed oil diets; only docosahexaenoic acid (22:6n-3, DHA) was not significantly increased. In most of the previous studies, the use of n-3 PUFA-rich vegetable oils showed no or only small effects on the intramuscular DHA level [7,15,21,22]. Feeding linseed oil-containing HPD- and RPD diets significantly decreased the concentration of single and total n-6 PUFA in longissimus muscle of pigs compared with the sunflower seed oil-containing fed groups and the control group (Table 5 and Figure 1). Consequently, the high level of n-3 PUFAs, which are beneficial for human nutrition, and the lower level of n-6 PUFAs in pigs fed linseed oil-containing diets caused a beneficially low n-6/n-3 PUFA ratio in the muscle compared with sunflower seed oil containing diets and the control diet. The n-6/n-3 PUFA ratio was 1.8:1 in muscle of pigs fed linseed oil containing HPD- and RPD diets, which corresponds to the n-6/n-3 PUFA ratio recommended by the German Nutrition Society (≤5:1) [23]. The concentrations of single saturated and total saturated fatty acids (SFA) were not affected by either the protein content or the type of oil supplement (Table 5 and Figure 1). Other studies showed that feeding a low protein diet with an increased IMF level resulted in elevated concentrations of 14:0, 16:0 and total SFAs, as a reflection of the higher IMF contents [19]. Additionally, oleic acid (18:1cis-9), the most abundant fatty acid in pig muscles, and total monounsaturated fatty acids (MUFAs) were not affected by the different dietary treatments.

Bottom Line:
In contrast to other studies, the intramuscular fat content (IMF) did not increase in animals of groups fed a reduced protein diet and vegetable oils.The growth performance and meat quality of the longissimus muscle was not affected by the diet, but the average daily gain (ADG) and drip loss were affected.The muscle fatty acid concentrations were significantly affected by the diet, resulting in higher n-3 FA concentrations up to 113 mg/100 g muscle and lower n-6/n-3 PUFA ratio for pigs fed linseed oil-containing high- and reduced protein diets, compared to sunflower seed oil-containing diets.

ABSTRACTThe present study investigated the effect of a reduced protein diet in combination with different vegetable oils (sunflower seed oil or linseed oil) on carcass traits, meat quality and fatty acid profile in porcine muscle. Forty male Landrace pigs were allocated into four experimental groups (each n = 8) and one control group (n = 8) at a live weight of approximately 60 kg. The pigs were fed ad libitum from 60 kg to 100 kg live weight and restricted to 2.8 kg/day until they reached 120 kg. In contrast to other studies, the intramuscular fat content (IMF) did not increase in animals of groups fed a reduced protein diet and vegetable oils. The IMF ranged between 1.2% and 1.4%. The growth performance and meat quality of the longissimus muscle was not affected by the diet, but the average daily gain (ADG) and drip loss were affected. The muscle fatty acid concentrations were significantly affected by the diet, resulting in higher n-3 FA concentrations up to 113 mg/100 g muscle and lower n-6/n-3 PUFA ratio for pigs fed linseed oil-containing high- and reduced protein diets, compared to sunflower seed oil-containing diets.